An example of such a mechanism may be that for mounting a side mounted gun sight to a gun wherein the gun and sight are aligned, i.e. boresighted, for a specific distance at which a line drawn longitudinally through the gun barrel intersects a line drawn longitudinally through the gun sight at that distance. Previous methods of coupling the two interfacing sections have required, at least to some degree, realignment. Which, to say the least, is unacceptable in many circumstances.